(1) Field of the Invention
The present invention relates generally to devices for remotely activating munitions, and more specifically to a remote digital firing system comprising a firing circuit, a firing control panel, and a digital code plug that is instrumental in generating and storing one-time random session variables at the firing circuit and securely transferring such session variables to the firing control panel for operation of the firing system. The present invention allows secure control of the remote digital firing system over the same insecure radio link as, for example, control of a mobile robot.
(2) Description of Related Art
Existing firing circuit control systems have required a separate communication channel to ensure safety. The present invention overcomes this limitation by allowing all aspects of a remote device to be controlled over a single communications channel while maintaining the safety of the firing system.
In addition, existing systems for switching the output relied upon discrete digital outputs from the microcontroller activating the switch devices (relays or FETs). This presents a risk in that failure of the microcontroller or software can activate the system. The present invention substantially reduces this risk and reduces the safety criticality of the embedded software.
Existing systems also have no provision to prevent a “replay attack,” where a hostile party can record the transmitted control signal while jamming the receiver, than play the recorded signal at a later time exposing personnel to harm.